The isolation, rapid identification and confirmation of Neisseria gonorrhoeae is of extreme importance in the diagnosis and treatment of the symptomatic and asymptomatic cases which are part of the worldwide gonorrhea epidemic. In addition early detection of disease is of utmost importance since undetected gonorrhea infections can lead to serious complications such as pelvic inflammatory disease, sterility, arthritis and blindness.
Infection with Neisseria gonorrhoeae requires different treatment than infections with other Neisseria species. Infections with nonpathogenic Neisseria such as N. flava, N. sicca, or N. subflava usually require no treatment, whereas infection with pathogens such as N. meningitidis may require different antibiotic therapy than N. gonorrhoeae.
The identification of Neisseria gonorrhoeae, Neisseria meningitidis, and other Neisseria species in the clinical laboratory is usually accomplished by culture and the performance of carbohydrate metabolism tests. Isolates from the cervix, urethra, and rectum are generally not confirmed by a sugar utilization test because other Neisseria species are not generally found at these sites, but isolates from the throat and eye must be confirmed due to nongonococcal strains that give positive presumptive tests for the gonococcus. Confirmation by sugar utilization can be a slow, cumbersome procedure, since a pure culture is required, which can involve several subcultures; even then, results take from 4 hours to 2 days.
Agglutination and coagglutination assays have been developed which use either antibodies or specific lectins as a binder to sites of the gonococcus and are extremely rapid, usually less than fifteen minutes. These tests have limitations because a number of Neisseria strains other than the gonococcus are reactive with lectins, and quite often antibodies are reactive only if the organisms are boiled before being reacted. Monoclonal antibodies have been produced which are specific to the Protein I (principle outer membrane protein) of Neisseria gonorrhoeae, but because some of these monoclonals react with only specific serotypes, it is necessary to use a pool of these monoclonal antibodies to recognize all the serotypes.
Horrisberger et al in 1977 in Journal of Histochem & Cytochem 25:295 report the use of colloidal gold labeled antibodies in an immunoassay for mannan. A similar gold sol particle immunoassay, is described by Leuvering in U.S. Pat. No. 4,313,734 (1982). Colloidal gold labeled antibodies have been used extensively in histological studies and have been used in a passive agglutination assay format as described by Geoghegan et al in 1980 Journal of Immunological Methods 34:11.
Gefter et al in U.S. Pat. No. 4,459,361 (1984) discloses a ligand assay with one or two particulate reagents and filter, wherein agglutinated antibody coated dyed particles are separated from nonagglutinated particles by use of a controlled pore size membrane filter. Gould et al in U.S. Pat. No. 4,552,839 (1985) discloses using dyed particles ranging in size from 50 nm to 100 microns which are antibody coated and after reacting with a respective antigen the reactants are allowed to diffuse on a bibulous support where the agglutinated particles will become immobilized when they have reached a certain size and charge.